Montgomery residents who live north of the Beltway should continue to boil water before drinking, cooking and brushing their teeth today, but officials said water quality results expected late Wednesday afternoon may return life to normal.

Representatives of the Washington Suburban Sanitary Commission said tens of thousands of county residents living in northern Montgomery County, in areas like Gaithersburg, Germantown, Burtonsville, Olney, Derwood and Wheaton, were affected by the four water main breaks since Sunday.